Sewing-machine



C. M. ABERCROMBIE.

SEWING MACHINE.

APPLICATION FILED JUNEZO, 1916.

2 SHEETSSHEET 1.

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WITNESS. IIVVENTOI? A TTOR/VE Y C. M. ABERCROMBIE.

SEWING MACHINEI APPLICATION FILED IUNEZO, I916- Patented Apr. 27, 1920.

2 SHEETS-SHEET'Z.

CHARLES M. ABERCROMBIE, OF BRIDGEIORT, CONNECTICUT, AS$IGNUR TO THE SINGER MANUFACTURING COMPANY, AiiGRPORrhlTION OF NEW JERSEY.

SEWING-MAGHINE Specification of Letters Patent.

Patented Apr. 27, 1920.

Application filed June ieie. serial no. 104:,653.

To all whom it may concern:

lle it known that I, CHARLns M. ABER 01101115115, a citizen of the United States, re-

siding at Bridgeport, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Sewmg-h lachmes, of which the fol lowing is a specification, reference being had therein to the accompanying drawings. This invention relates to improvements in sewing machines employing a needle having which like parts are similarly designated,

Figure 1 is a view in elevation of a hemstitch sewing machine equipped with the present invention, the head of the armbracket being shown partly in section to better illustrate the means employed for giving to the needle its reciprocating movements. Fig. 1. Figs. 3, 1, 5 and 6 are views in elevation of the needle vibrating bar, the tubular needle carrying bar, the needle vibrating bar guide bracket and the needle vibrating bar yoke, respectively.

The invention is herein shown and will be described in connection with so much of one variety of Singer commercial hemstitch sewing machines as is deemed sufi'i-' meat for an understanding of its applica-.

tion, and is intended to comprise im oroved means over that represented by U. i Patent No. 72%,233, March 31, 1903, to the present inventor for controlling the stitch-forming movements of the needle.

1 represents the sewing machine bed-plate upon which is mounted the bracket-arm comprising the arm-bracket 2 and standard 3, 1 the mainorneedle-bar driving shaft mounted in suitable bearings formed in the bracket-arm and provided with the bandwheel 5, belt-pulley 6 (shown in dotted lines only), gear member 7' and shaft flange 8. 9 denotes the needle-thread take-up, 10 a link in the train of connections, common to the commercial machine previously referred to, for transmitting from the mainshaft reciprocating movements to the needle 11, and 1'2 the spring depressed cloth-presser Fig. 2 is a front end elevation of carrying bar which, in practice, is provided with suitable cloth-presser (not shown).

13 represents the needle vibrating bar, 1 1 the needle vibrating bar tubular guide, lathe tubular needle carrying bar and 16 thr vibrating bar oscillating yoke. To assemble the parts 13, 1 1, 15 and 16, as in Figs. 1 and 2, the yoke 16 is positioned between the lugs 17 and 18 of the head 19 of the arm-bracket and in line with the openings 21 and 22 in said lugs when the bar 15, after having removed the needlebar actuating collar 23, is passed up through the opening 2a in the yoke and the collar positioned and secured as in Fig. 4:, followed by positioning the guide 141 in the opening 25 of the yoke with the lugs as 2-6 tracking the groove 27 in said yoke when the bar 13 is passed up through the opening 28 in the bar 15 and through the opening 29 in the guide 1 1, after which the elements '13, 1 1 and 15 are moved downward sufficient to secure said guide on to the bar 13 by tightening the screws, as 30, the guide being positioned with respect to the collar 31, suitably secured on the lower end of the bar 13 and later to be referred to, to hold the bar 15 against lengthwise move ment on the bar 13, when the lower end of the link 10 is operatively connected with the bearing on the collar 23, as best illustratedin Fig. 1.

The gear member 7 carried by the mainshaft cooperates with the gear member 33 forming a part of the needle vibrating cam 3 1 provided with a cam-groove 35, said gear and cam member being mounted to rotateon a shaft 36 suitably secured in the standard 3 of the bracket-arm, the ratio of said gears being as 1 to 3, the same as is common to machines of the present class. 37 denotes the pitman actuatingdever provided with afulcrunrpin 38 journaled in a bushing 39 suitably'secured in the bracket arm, a collar 10 and set-screw 41 (shown in dotted lines only) acting to secure said fulcrum pin against accidental endwise movement, the lever 37, at its lower end, being provided with a stud 412, and camroller 13 (the elements 42 and 13 being shown in dotted lines only), the latter tracking the cam-groove 35, thus giving to the lever 37 oscillatory movements.

49 represents the pitman bracket adjustably secured by screw 50 in a guide-way 51 formed in the lever 37, said bracket having secured to it by the suitably secured cap 52 ,one end or" a spiral spring 53 whose opposite end is suitably secured in the pitman 54, the front end of the latter carrying a like suitably secured spring 55 whose opposite end is secured to the yoke 16 by the suitably secured cap 56, thus transmitting from the cam-groove 35, through the connecting elements pointed out, rocking movements to the yoke 16, the latter transmitting through the guide 14;, oscillatory movements to the bar 13.

In the construction of the pitman 5d the spiral springs 53 and are preferably formed with the coils of wire in juxtaposed relationship, and the co-eiilcient of elasticity of each spring in the direction of its length is such that the resistance to strain is in excess of the capacity of the motive power required to actuate the driven element.

57 represents a pinch collar secured by screw 58 to the lower end of the tubular bar 1.5, said collar being provided with a bearing stud 59 upon which pivotally secured by screw (30 a needle carrying bracket 61 into which is suitably secured the needle 11. Into the collar 31 fast on the oscillating bar 13 is secured a driving element comprising pins, as 62, arranged one at one side and the other at the opposite side of the bracket (51, said pins through the oscillatory movements of the bar 13 transmitting lateral movements to the needle 11, thus effecting reciprocatory movements of the latter in different paths.

In the present, as in commercial sewing machines for effecting a true hem-stitch figure, the feed-dog 64; is actuated to give to the fabric two feed movements forward and one return feed movement for each hemstitch figure and the cam-groove 35 of the cam 3 f for giving to the needle its lateral movements is constructed and actuated to effect two descents of the needle in like paths and one descent in a different path.

Having thus set forth the nature of the invention, what I claim herein is 1. In a sewing machine, in combination, a needle-bar, means for imparting endwise reciprocations to said needle-bar, a needlecarrying bracket sustained by said needlebar, a needle-vibrating bar arranged telescopically with respect to the needle-bar and projecting beyond the upper end of the lat- O ter, a yoke having spaced bearings of which one bearing is journaled upon said needlebar and the other bearing is sustained by said needle-vibrating bar, means for vibrating said yoke from said actuating shaft, operative connections between the secondnamed bearing of said yoke and said needlevibrating bar for oscillating the latter, and

operative connections between the needlevibrating bar and the needle whereby the means for vibratin said oke means rovided upon said yoke coacting with said guide whereby vibratory movement of the yoke imparts oscillatory movement to said needle vibrating bar, and means whereby the oscillating needle-vibrating bar imparts lateral movements to the needle.

In a sewing machine, in combination, a needle-bar, a needle-carrying bracket fulcrumed upon said needle-bar, means for imparting endwise I reciprocations to said needle-bar, a needle-vibrating bar arranged telescopically within said needle bar, a vibrator yoke journaled coaxially with the needle-vibrating bar, means for. vibrating said yoke, a guide secured upon the needlevibrating bar adjacent and beyond one end of the needle-bar, a driving element secured upon said needle-vibrating bar adjacent the opposite end of the needle-bar coacting with said guide to restrain the needle-vibrating bar against relative endwise movement with respect to the needle-bar, and means provided on said yoke coacting with said guide for oscillating the needle-vibrating bar.

In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.

' CHARLES M. ABEli-CROMBIE.

Witnesses W. A. SAUTTER, FRANK M. WOOTTON. 

